Vehicle travel controlling apparatus and method

Abstract

A vehicle travel controlling apparatus and method in which a target vehicle speed for when a vehicle travels along a curve is calculated based on a radius of the curve, and the vehicle speed is controlled based on the calculated target vehicle speed. When an accelerator operation performed by a driver is detected, the controller corrects the target vehicle speed based on a vehicle position where the acceleration operation is performed.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The description herein makes reference to the accompanying drawings wherein like reference numerals refer to like parts throughout the several views, and wherein:

FIG. 1 shows a structure of a vehicle travel controlling device according to a first embodiment;

FIG. 2 is a flowchart of the steps of a controlling process that is performed by the vehicle travel controlling device according to the first embodiment;

FIG. 3 shows an example of road data that is read out from a map database;

FIG. 4 shows a radius of a circle that passes through three nodes, nodes Nk−1, Nk and Nk+1;

FIG. 5 shows a relationship between the distance from a current position of a vehicle and the vehicle speed at which the vehicle can pass along a curve;

FIG. 6 is a flowchart of the steps of correcting a target deceleration;

FIG. 7 shows a default target vehicle speed for when the vehicle travels into a curve and a target vehicle speed for when a driver operates an accelerator pedal at a point occupied before entering an entrance of the curve and that is disposed at a distance equal to or greater than a predetermined distance from the curve entrance;

FIG. 8 shows a default target vehicle speed for when the vehicle travels into the curve and a target vehicle speed for when the driver operates the accelerator pedal at a point that is situated within a predetermined distance from the entrance of the curve;

FIG. 9 shows a default target vehicle speed for when the vehicle travels into the curve and target vehicle speeds for when the driver operates the accelerator pedal at an interval from the entrance of the curve to a point where a curve radius is a minimum and at an interval from the point where the curve radius is a minimum to an exit of the curve;

FIG. 10 shows a change in the vehicle speed when the driver depresses the accelerator pedal at a point within a predetermined distance from the exit of the curve (e.g., near the exit of the curve) when a deceleration control is operated;

FIG. 11 is a flowchart of the steps of calculating a vehicle speed command value;

FIG. 12 is a flowchart of the steps of correcting a target deceleration in a vehicle travel controlling device according to a second embodiment;

FIG. 13 shows a structure of a vehicle travel controlling device according to a third embodiment; and

FIG. 14 shows an example of a relationship between a lateral acceleration αYK obtained by computation and a lateral acceleration αSNS detected by a lateral acceleration sensor.

Claims

1. A control apparatus for a vehicle, the apparatus comprising: a vehicle position detector configured to detect a traveling position of the vehicle;an accelerator operation detector configured to detect an accelerator operation by a driver; anda controller operable to: calculate a target vehicular speed for cornering a curve in a path of the vehicle based on a radius of the curve;correct the target vehicular speed based on the traveling position where the accelerator operation is detected by the accelerator operation detector; andcontrol a vehicular speed based on the target vehicular speed.

2. The control apparatus according to claim 1 wherein the accelerator operation detector is further configured to detect an amount of the accelerator operation; and wherein the controller is further operable to: correct the target vehicular speed based on the traveling position where the accelerator operation is detected by the accelerator operation detector and the amount of the accelerator operation detected by the accelerator operation detector.

3. The control apparatus according to claim 2 wherein the controller is further operable to: correct the target vehicular speed after the acceleration operation such that a larger the amount of the accelerator operation, a smaller a degree of deceleration for the control of the vehicular speed.

4. The control apparatus according to claim 3 wherein the controller is further operable to: calculate an accelerator release speed; andend correction of the target vehicular speed when the accelerator release speed is equal to or greater than a predetermined speed.

5. The control apparatus according to claim 2 wherein the amount of the accelerator operation is based on at least one of an amount of depression of an accelerator, a time integration value of the amount of the depression of the accelerator, and a number of depressions of the accelerator.

6. The control apparatus according to claim 2 wherein the controller is further operable to: correct the target vehicular speed after the accelerator operation such that a closer the position when the accelerator operation is detected is to an exit of the curve, a larger a degree of acceleration for the control of the vehicular speed.

7. The control apparatus according to claim 1 wherein the accelerator operation detector is further configured to detect an amount of the accelerator operation; and wherein the controller is further operable to: determine a precision with which the traveling position is detected by the vehicle position detector;compare the precision to a predetermined precision; andcorrect the target vehicular speed in accordance with the amount detected by the accelerator operation detector when a next target vehicle speed is calculated when the precision is equal to or greater than the predetermined precision.

8. The control apparatus according to claim 7, further comprising: a lateral acceleration detector configured to detect an actual lateral acceleration of the vehicle when the vehicle passes along the curve; and wherein the controller is further operable to: calculate an estimated lateral acceleration of the vehicle, prior to when the vehicle passes along the curve, for when the vehicle passes along the curve, the estimated lateral acceleration based on the radius of the curve; andcompare the precision to the predetermined precision based on the estimated lateral acceleration and the actual lateral acceleration.

9. The control apparatus according to claim 1 wherein the controller is further operable to: calculate the target vehicular speed in a first section from a location before entering the curve to an exit of the curve;control at least one of deceleration and acceleration of the vehicle based on the target vehicular speed; andcorrect the target vehicular speed after the accelerator operation is detected such that a larger an amount of the accelerator operation, a larger a degree of acceleration for the control of the vehicular speed.

10. The control apparatus according to claim 1 wherein the controller is further operable to: correct the target vehicle speed for after the accelerator operation such that a closer the traveling position where the accelerator operation is detected is to an exit of the curve, a smaller a degree of deceleration for the control of the vehicle speed.

11. The control apparatus according to claim 1 wherein the traveling position where the accelerator operation is detected is at least one of a vehicle position when the accelerator operation is started, a vehicle position when the accelerator operation is completed and a section of the curve at which an accelerator pedal is operated.

12. The control apparatus according to claim 1, further comprising: a plurality of sections forming the curve; and wherein the controller is further operable to: correct the target vehicular speed based on which of the plurality of sections the traveling position where the accelerator operation is detected occurs.

13. The control apparatus according to claim 12 wherein the plurality of sections forming the curve comprises a first section occupied before entering a curve entrance, a second section between the curve entrance and a point where the radius of the curve is a minimum and a third section between the point where the radius of the curve radius is a minimum and an exit of the curve.

14. The control apparatus according to claim 1, further comprising: a plurality of sections forming the curve; and wherein the controller is further operable to: increase the target vehicle speed at all sections of the curve when the driver performs the acceleration operation when the radius of the curve is equal to or greater than a predetermined value.

15. A control apparatus for a vehicle, the apparatus comprising: means for detecting a traveling position of the vehicle;means for detecting an accelerator operation by a driver;means for calculating a target vehicular speed for cornering a curve in a path of the vehicle based on a radius of the curve;means for correcting the target vehicular speed based the traveling position where the accelerator operation is detected by the accelerator operation detecting means; andmeans for controlling a vehicular speed based on the target vehicular speed.

16. A control method for a vehicle, the method comprising: detecting an accelerator operation by a driver;calculating a target vehicular speed for cornering a curve in a path of the vehicle based on a radius of the curve;correcting the target vehicular speed based on a position of the vehicle with respect to the curve, the position occurring when the accelerator operation by the driver is detected; andcontrolling a vehicular speed based on the target vehicular speed.

17. The control method according to claim 16, further comprising: detecting an amount of the accelerator operation; and wherein correcting the target vehicular speed further comprises correcting the target vehicular speed based on the position and the amount.

18. The control method according to claim 17 wherein correcting the target vehicular speed based on the position and the amount further comprises correcting the target vehicular speed such that a larger the amount, a smaller a degree of deceleration.

19. The control method according to claim 16, further comprising: calculating an accelerator release speed; andending correcting the target vehicular speed when the accelerator release speed is equal to or greater than a predetermined speed.

20. The control method according to claim 16 wherein correcting the target vehicular speed further comprises correcting the target vehicular speed such that a closer the position is to an exit of the curve, a larger a degree of acceleration.